Double boring-machine.



a No. 840,528. PATENTED JAN. 8, 1907.

' J. T. TOWSLEY.

DOUBLE BORING MACHINE.

APPLICATION FILED 00124. 1906.

2 SHEETS-SHEET 1.

gmmntoz No. 840,528. PATENTED JAN. 8-, 190'7.

' J. T. TOWSLBY.

DOUBLE BORING MACHINE.

APPLICATION FILED OUT- 24. 1906.

2 SHEETS-SHEET 2- I f d/ d alwenfoz Witnemea 6. aww' UNITED STATES PATENT OFFICE.

Specification of Letters 'Patent.

' Patented Jan. 8, 1 907.

Application filed October 24:, 1906. Serial No. 340,266.

To all whom it may concern:

Be it known thatl, JOHN T. TOWSLEY, a citizen of the United States of America, and aresident of Cincinnati, county of Hamilton, State of Ohio, have invented certain new and useful Improvements in Double Boring-Machines, of which thefollowing is a specification.

' In boring-machines of the kindto which this invention relates the work is held upon a horizontal table. One of the boring-spindles is fixed, and the other boring-spindle is mounted so as to be rotatableabout the fixed spindle and to be adjustable to different distances therefrom. The fixed spindle is directly driven. A large gear-wheel is mounted so as to change position with the movable boring-spindle I to I keep it in gear with the fixed spindle.

The object of my invention is to provide a means for automatically counterbalancing the; pressure of the large gear-wheel against the movable boring-spindle in proportion as the pressure changes with difierent positions ofthese parts. This object is attainedby the means illustrated in the accompanying drawings, in which Figure 1 is a rear elevation of a boring-machine embodying my invention, showing the saddle-bed in its horizontal position. Fig. .2 is a view similar to Fig. 1, bu t showing the saddle bed in its vertical position, parts of the machine being broken away and omitted which have no particular bearing upon the present invention. Fig. 3 is aplan view of my invention. Fig. 4 is a sectional view on line :20 :r of Fig. 3.

Table A, upon which the work is held, is mounted upon column B, so as to be movable toward the boring-spindles in the customary manner. The fixed boring-spindle C is j ournaled in brackets 19 and. b, which are secured, respectively, to the front and rear of the column B. The top of the column B has a semicylindrical depression, into which fits a semicylindrical segment D, which has a slot 01, through which a bolt d passes into the column to hold the segment D in the relative position to its seat in the column to which it has been adjusted, this locking being accomplished by means of lever 01 in the usual manner. The fixed spindle C is located in the axis of the segment D. To the segment D is secured the saddle-bed d upon which the saddle d is'movable by means of the feedscrew d so as to move the saddle toward and away from the fixed spindle D. Saddle d has journal-boxes d and d7, in which the movable boringspindle E is journaled. When the saddle has been adjusted to the position desired, it is locked by means of the clamp (i Bracket b has a collar b concentricwith the fixed spindle C, upon which is journaled a yoke F, which contains a cylindrical box f, fitting over the collar 1) and held thereon by means of a ring f secured to the box and projecting down over the inside of the collar- Box f has projecting'froniit a straight a'rmf and an L-shaped armf be tween which a shaft 9 is journaled. Shaft g carries a large gear-wheel G, whichmeshes with gear-teeth e and 0, cut, respectively, upon the movable and upon the fixed boringspindles E and 0. Upon shaft 9 is journaled an arm H, the opposite end of which is j ournaled upon the end of the boring-spindle E. The fixed spindleO carries a pulley c, which receives the driving-belt. I

In the operation of this double boring-machine as thus far described it is seen that rotation is conveyed from the fixed spindle 0 through the large gear G to the movable spindle E. When it is desired to change the vertical' distance of the movable spindle above the table A, this is accomplished by rotating the segment Din the top of the column,

which carries the saddle-bed from a horizontal to vertical position or to any position be tween a horizontal and a vertical position. In moving the bed in this manner it is seen that the yoke F revolves about the bracket I), always keeping the large gear G in mesh with the teeth e and c. When the saddle is moved toward or from the fixed spindle to change the relative positions of the two boring-spindles, it is seen that the arm H likewise causes the yoke F to revolve the bracket b. I w

It is seen that the weight of the large gearwheel G has a tendency to force the boringspindles apart and that this tendency increases with the distance apart of the boring spindles and with the distance which the saddle-bed occupies from its vertical position. To counterbalance this varying pressure of the large gear-wheel G, I have provided the following mechanism:

Box of the yoke has upon its exterior gear, teeth Beneath the box f I have mounted a sprocket-wheel K upon an adjustable stud k, which projects through bracket 1;. Con

necting sprocket-wheel K and the gear-teeth upon the box f is a sprocket-chain 7c J ournaled upon the stud 7c is an arm 70 which projects from the stud k in a direction diametrically opposite to that in which the arm f projects. Arm k is fastened by a bolt k to the sprocket-wheel K and carries at its end a weight k. The weight k creates a tendency in the sprocket-Wheel K to rotate in a direction opposite to that in which the weight of the gear-wheel G tends to rotate the yoke. The length of the lever-arm of the weight k is seen to be greatest when the arm f approaches its horizontal position, which is the position in which the gear-wheel Ghas a tendency to exert greatest pressure upon the spindle E, and that as the arm f approaches the vertical position the length of the leverarm of the weight 12' decreases, so that as the pressure of the gear-wheel G decreases the tendency of the weight to rotate the sprocket- Wheel K decreases. When the arm f passes beyond the vertical position, as shown in Fig. 2, it is seen that the tendency of the large gear-wheel G is no longer exerted toward forcing the spindles apart, but tends to draw them together, and that this tendency likewise is overcome by the weight 7%, which tends to move the yoke in a direction so as to separate the boring-spindles. The varying pressure of the gear-wheel G upon the spindle E is thus automatically counterbalanced.

What I claim. is

1. In a boring-machine the combination of boring-spindles mounted so as to be ad justable toward and away from each other, gear-teeth upon the spindles, a gear-wheel mounted so as to move with the spindles and to keep in mesh with the teeth thereon, and an automatic counterbalance for the weight of the gear-wheel against the spindles.

2. In a boring-machine the combination of -a fixed boring-spindle, a boring-spindle mounted to revolve about the fixed spindle, teeth upon the spindles, a yoke revoluble about the fixed spindles, a gearwheel carried by the yoke to mesh with the teeth upon the spindles, and a counterbalance connected to the yoke for the weight of the gear-wheel against the spindles.

8. In a boring-machine the combination -:f a fixed boring spindle, a saddle bed mounted to revolve about the fixed spindle, a saddle mounted reciprocally upon the bed, a spindle journaled in the saddle, teeth upon the spindles, a yoke mounted revolubly about the fixed spindle having outwardly-projecting arms, a gear-wheel journaled between the arms of the yoke and in mesh with the teeth upon the spindles, an arm pivoted at one of its ends to the yoke and at the other of its ends to the saddle, and a counterbalance carried by the yoke for the weight of the gearwheel against the spindles.

4. In a boring-machine the combination of a fixed boring spindle, a saddle bed. mounted to revolve about the fixed spindle, a saddle mounted reciprocally upon the bed, a spindle journaled in the saddle, teeth upon the spindles, a yoke mounted revolubly about the fixed spindle having outwardlyprojecting arms, a gear-wheel j ournaled between the arms of the yoke and in mesh with the teeth upon the spindles, an arm pivoted at one of its ends to the yoke and at the other of its ends to the saddle, gear-teeth upon the yoke, a sprocket-wheel mounted adjacent to the yoke, a chain connecting the yoke and the sprocket-wheel, an arm secured to the sprocket-wheel and a weight carried by the arm to counterbalance the weight of the gear-wheel upon the spindles.

JOHN T. TOVVSLEY.

Witnesses:

WALTER F. MURRAY, AGNES, McCoRMAoK. 

